Self-destructive irreversible security packaging film

ABSTRACT

A self-destructive irreversible security packaging water soluble film and method for manufacturing the same. The water soluble packaging film is embedded with various security elements, which will get irreversibly destroyed upon final usage as the whole package along with its contents will dissolve in water. This process of self-destruction will control the duplication of the package or alteration of the product inside the package.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a divisional of co-pending application Ser. No. 11/918,516 filed Oct. 15, 2007, which in turn is the US National Stage of International App. No. PCT/IN2006/000133 filed Apr. 17, 2006, which claims priority to Indian Pat. App. No. 469/MUM/2005, filed Apr. 15, 2005, all of which are incorporated herein by reference.

FIELD OF THE INVENTION

The invention relates to a self-destructive irreversible security packaging water soluble film and method for manufacturing the same. The water soluble packaging film is embedded with various security elements, which will get destroyed irreversibly upon final usage as the whole package along with its contents will dissolve in water. This process of self-destruction will control the duplication of package or alteration of the product inside the package.

BACKGROUND OF INVENTION

Securing a product like pesticides, agrochemicals, cosmetics, etc. have been in urgent need by the industry. Simulation, alteration and duplication of genuine products have always been rampant in today's world. No forceful solution has been found to ensure that the security package itself gets used up every time the end product/content is being consumed.

There have been several methods of securing a product by means of printing security tracers, or by affixing varied OVDs like holograms, or color shifting inks etc. But these are usually on packages. Once the package is successfully opened, the original product can be replaced by a duplicate and the resultant product can be brand damaging and may lead to legal suits. Many times the package is discarded after the contents are used and this same package becomes a target for unlawful duplication.

There have been several attempts in the past to either encase or laminate or package different security elements in films, but none have proved fool proof and successful for such varied end uses.

One such patent WO 2004048113 relates to a blister film partially applied with security feature. The application of the security features ensues by detaching the security feature from a supporting substrate, which is provided with a UV-curable separating paint that is capable of being deep-drawn.

Here, the blister film with security feature can be tampered or a discarded package can be reused for packaging a duplicate product.

It is a long-standing need of industry to develop efficient and cost effective methods for the manufacture of fool proof security package for controlling piracy, simulation, alteration or duplication of original products in diverse applications and especially an unique all-encompassing packaging film that is capable of irreversibly destroying itself. Further the need for carriers that can selectively carry combination of materials with dissimilar properties such as miscible/immiscible, hydrophobic/hydrophilic security materials continues to elude the industry.

The present invention relates to a security package which has inbuilt embedded security elements which form a part of the package itself. This package is not needed to be opened, and is self-destructing. The package itself is part of the product and delivers the security features. After the final usage of package, the packaging material including security elements are self-destroyed irreversibly. The security elements and genuineness of the product/package can be verified, while it is on the shelf of distribution as well as off the shelf. The security elements may be traceable, if need arises, even after the security package and its contents have been consumed or delivered to desired location (e.g. soil, laundry) after the same has been dissolved in water.

The invention addresses various problems and also reduces costs and ensures that fraudsters are brought to book legally and action taken against them. It also ensures that new products and brands get their true value by ruling out any tampering, duplication and alteration of the product.

SUMMARY OF THE INVENTION

The main object of the invention is to provide a self-destructive irreversible security packaging water soluble film to prevent duplication, alteration and simulation of the packed products.

Another object of the invention is to embed one or more security elements with similar and/or dissimilar properties into one or more layers of WSF to form a multi-layered WSF embedded with security features.

Yet another object of the invention is to provide the method of manufacturing a self-destructive irreversible security packaging water soluble film wherein one or more security elements with similar and/or dissimilar properties are embedded into one or more layers of WSF to form a multi-layered WSF embedded with security elements.

As per the invention there is provided a self-destructive irreversible security packaging water soluble film (WSF) for packages or the like, comprising one or more layer(s) of water soluble film and at least one inbuilt security element embedded or entrapped or imparted in at least one layer of the WSF forming a part of the security package which will destroy itself irreversibly during final usage after dissolving or dispersing in water.

As per the invention there is provided a security packaging WSF, wherein more than one security element of similar and/or dissimilar properties is embedded/entrapped or imparted in one or more layers of the WSF.

The WSF is a single layered or multi-layered film made of raw materials selected from Polyvinyl alcohol copolymer ionomers, Polyvinyl alcohol homopolymer, non-ionomeric polyvinyl alcohol polymer, Polymethacrylate, polyvinyl alcohol, polyacrylamide, polymethacrylamide, polyacrylic acid, polymethacrylic acid, polyurethane, polyethyleneglycol, polyvinylpyrrolidone, proteinaceous binders such as gelatin, modified gelatins such as phthaloyl gelatin, polysaccharides such as starch, gum Arabic, pullulan and dextrin and water-soluble cellulose derivatives such as methyl cellulose, hydroxy propyl cellulose, hydroxy propyl methyl cellulose, hydroxy propyl ethyl cellulose, hydroxy ethyl cellulose, carboxy methyl cellulose either alone or combinations thereof.

The WSF is cold water soluble, warm water soluble, hot water soluble or non-soluble depending upon the formulation.

The security element(s) is/are of overt nature or of covert nature and are selected from optically variable pigments, multi-layer thin-film interference pigments, liquid crystal pigments, holographic pigments, interference coated particles, thermochromic pigments, photochromic pigments, luminescent compounds, magnetic compounds, infrared-absorbing compounds, UV-absorbing compounds, magnetic compounds, micro-engraved or microtextured flake pigments, forensic marking compounds, dyes, RFID taggants, nano particles, nano tracers, security markers printed security features like barcodes, metallized fibers, metallized/demetallized texts, active molecules, DNA taggants and the like.

The security element(s) is/are light source readable, machine readable PCR or otherwise readable by any mechanical, electrical or digital device.

The security elements, like holograms, barcodes, metallized/demetallized microtexts are printed or embossed on the WSF forming a part of the WSF.

The security packaging WSF can be converted into self-adhesive web and further converted into a printed seal with a barcode including 2D or 3D barcode forming self-adhesive label/seal used for securing the openings of a package or a bottle.

As per the invention there is provided a method of manufacturing self-destructive irreversible security packaging WSF comprising following steps:

-   -   a. providing a formulation of said water soluble film,     -   b. casting said formulation to form a water soluble film,     -   c. embedding/entrapping at least one desired security element in         said formulation of the water soluble film prior to and/or after         casting the water soluble film; and     -   d. drying the film with the embedded security elements.

As per the invention there is also provided a method of manufacturing self-destructive irreversible security packaging WSF comprising adding the security element(s) into at least one batch mixer containing batch solution of the WSF, mixing thoroughly and feeding to the primary or subsequent casting heads for further processing in a known manner to achieve security element(s) embedded WSF.

As per the invention there is also provided a method in which the security element(s) is/are introduced at the primary, secondary, tertiary or subsequent sprayers to achieve security element(s) embedded WSF.

As per the invention there is also provided a method of manufacturing security packaging WSF comprising the following steps:

-   -   a. unwinding a liner from an unwinder of the WSF casting         machine,     -   b. mixing security element(s) with the WSF raw materials batch         solution in a batch mixer,     -   c. casting WSF on the liner at the primary casting head of the         casting machine, with embedded security element(s) and metering         and smoothening the same,     -   d. drying the WSF with embedded security element(s) in the         primary dryer section,     -   e. casting of another layer of WSF with or without the security         element(s) embedded therein, at secondary casting head of the         casting machine,     -   f. drying the multilayered WSF with embedded security element(s)         in a secondary dryer section,     -   g. guiding the film of step (f) through hot chilled cylinder and         rewinding or splitting at the rewinder.

As per the invention there is also provided a method of manufacturing security packaging WSF comprising the following steps:

-   -   a. unwinding a liner from an unwinder of the WSF casting         machine,     -   b. casting of WSF on the liner with or without the security         element(s) at the primary casting head and metering the cast         film,     -   c. spraying the security element(s) by primary sprayer and         smoothening the film,     -   d. drying the WSF of step (c) at the primary dryer section,     -   e. casting another layer of WSF with or without the security         element(s) at secondary casting head,     -   f. drying the WSF with embedded security element(s) at the         secondary dryer section,     -   g. guiding the multilayered WSF with embedded security         element(s) of step (f) through hot cylinder for rewinding or         splitting at a rewinder,

As per the invention there is also provided a method of manufacturing security packaging WSF comprising of the following steps:

-   -   a. unwinding a liner from an unwinder of a WSF casting machine,     -   b. casting WSF with or without security element(s) and metering         and smoothening the same,     -   c. drying the WSF of step (b) in the primary dryer section,     -   d. casting another layer of WSF with or without the security         element(s) at a secondary casting head,     -   e. drying the WSF of step (d) in the secondary dryer section,     -   f. unwinding a preformed WSF with or without liner from another         unwinder and guiding it to meet the WSF from step (e),     -   g. entrapping security element(s) between the semi-cured WSF of         step (e) and the preformed WSF,     -   h. guiding the multilayered WSF with entrapped security         element(s) through hot cylinder for rewinding or splitting at a         rewinder.

As per the invention there is also provided a method of manufacturing security packaging WSF comprising the following steps:

-   -   a. unwinding two WSFs with or without the liners from two         unwinders,     -   b. dispensing the security element(s) in between the two WSFs;     -   c. rewinding the multilayered WSF with entrapped security         element(s) in roll form or sheet form or fan-fold form.

The security element(s) is/are dispensed in between the two incoming cured, semi-cured or uncured WSFs in vertical position or horizontal position.

The preformed WSFs used here can be water soluble films produced by a cast process or extrusion process.

The liner used is treated or untreated and coated or uncoated and is of paper, film, foil or fabric.

The WSF can also be cast on a conveyor instead of a liner.

As per the invention there is also provided a method, in which WSF is cold water soluble, warm water soluble, hot water soluble or non-soluble depending upon the formulation formed from raw materials selected from Polyvinyl alcohol copolymer ionomers, Polyvinyl alcohol homopolymer, non-ionomeric polyvinyl alcohol polymer, Polymethacrylate, polyvinyl alcohol, polyacrylamide, polymethacrylamide, polyacrylic acid, polymethacrylic acid, polyurethane, polyethyleneglycol, polyvinylpyrrolidone, proteinaceous binders such as gelatin, modified gelatins such as phthaloyl gelatin, polysaccharides such as starch, gum Arabic, pullulan and dextrin and water-soluble cellulose derivatives such as methyl cellulose, hydroxy propyl cellulose, hydroxy propyl methyl cellulose, hydroxy propyl ethyl cellulose, hydroxy ethyl cellulose, carboxy methyl cellulose either alone or combinations thereof.

As per the invention there is also provided a method, in which the security element(s) is/are of overt or covert nature and is/are selected from optically variable pigments, multi-layer thin-film interference pigments, liquid crystal pigments, holographic pigments, interference coated particles, thermochromic pigments, photochromic pigments, luminescent compounds, magnetic compounds, infrared-absorbing compounds, UV-absorbing compounds, magnetic compounds, micro-engraved or microtextured flake pigments, forensic marking compounds, dyes, RFID taggants, nano particles, nano tracers, security markers printed security features like barcodes, metallized fibers, metallized/demetallized texts, active molecules, DNA taggants.

The WSF embedded with security element(s) can be slit in ribbons, tapes, perforated sheets, perforated tapes, perforated ribbons or cut sheets of any size.

The WSF embedded with security elements slit into ribbons, tapes, etc. can be inserted into a package during the process of making pouch. The ribbons, tapes, etc. will destroy itself irreversibly during the final usage when the entire pouch along with its contents will dissolve itself in water.

The WSF embedded/entrapped with security element(s) is in sheet form or roll form or pouch form as per the end use.

As per the invention there is also provided a method of manufacturing security packaging WSF comprising overt security element(s) like holograms embedded into the WSF by directly embossing a holographic plate on WSF preferably with liner which can be detached after the process of embossing.

The holograms are imprinted/imparted on the WSF with hot stamping foil method or by adhesive transfer method.

Other overt security element(s) like barcodes, microtexts are embedded in the WSF by printing them on WSF itself by known printing methods such as inkjet, flexo, gravure, web offset and the like.

As per the invention there is also provided a method of manufacturing security packaging WSF comprising mixing of security element(s) in the printing ink and printing letters or graphics on WSF with the printing ink consisting security element(s), forming a part of WSF itself.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic drawing of a method in accordance with the present invention.

FIG. 2 is a schematic drawing of an alternative method in accordance with the present invention.

FIG. 3 is a schematic drawing of another alternative method in accordance with the present invention.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

The invention will now be described in detail with reference to accompanying drawings showing various embodiments:

The materials of the WSF formulation is taken in the batch reactor and mixed intimately to ensure complete dissolution in the desired solvent.

The raw materials used for making the water soluble film are selected from Polyvinyl alcohol copolymer ionomers, Polyvinyl alcohol homopolymer, non-ionomeric poly vinyl alcohol polymer, Polymethacrylate, polyvinyl alcohol, polyacrylamide, polymethacrylamide, polyacrylic acid, polymethacrylic acid, polyurethane, polyethyleneglycol, polyvinylpyrrolidone, proteinaceous binders such as gelatin, modified gelatins such as phthaloyl gelatin, polysaccharides such as starch, gum Arabic, pullulan and dextrin and water-soluble cellulose derivatives such as methyl cellulose, hydroxy propyl cellulose, hydroxy propyl methyl cellulose, hydroxy propyl ethyl cellulose, hydroxy ethyl cellulose, carboxy methyl cellulose either alone or combinations thereof. However, these raw materials are by no means limiting. The water soluble films can be cold water soluble, warm water soluble, hot water soluble or non-soluble depending upon the formulation.

The preformed WSF used in the present invention can be a cast film or an extruded film depending upon the end application.

The security elements to be embedded into the WSF can be selected from optically variable pigments, multi-layer thin-film interference pigments, liquid crystal pigments, holographic pigments, interference coated particles, thermochromic pigments, photochromic pigments, luminescent compounds, magnetic compounds, infrared-absorbing compounds, UV-absorbing compounds, magnetic compounds, micro-engraved or microtextured flake pigments, forensic marking compounds, dyes, RFID taggants, nano particles, nano tracers, security markers printed security features like barcodes, metallized fibers, metallized/demetallized texts, active molecules, DNA taggants and the like.

Some of these security elements are of overt nature or of covert nature which can be identified on the shelf or off the shelf depending upon the security elements embedded in the WSF.

Covert security elements are the ones that are not visible and will require a particular instrument for verifying the same. E.g. pigments, dyes, nano particles, nano tracers, active molecules DNA taggants, and the like.

A WSF package embedded with covert security elements like invisible inks or dyes can be identified on the shelf under an ultra violet (UV) (long wave) fluorescing light source.

A WSF package embedded with covert security elements like nano particles can be identified on the shelf with the help of a 100× magnifying glass.

Some covert security elements can be identified off the shelf only as the package has to be taken to a laboratory having elaborate instruments and machines so as to read the embedded covert security elements. There may be a need to destroy the package in some cases. E.g. certain pigments which are Infra-Red light readable with an algorithm of software chain designed to read the reflected light and confirm the presence of such pigments/dyes/security elements or magnetic field readable pigments embedded in nano particles which give an audible beep when the machine reader reaches the precise proximity etc.

Overt security elements are the ones that are visible and can be identified on the shelf almost instantaneously without need of an elaborate laboratory instruments or machines. E.g. holograms, barcodes, metallized/demetallized micro texts, RFID tags and the like. These kind of security elements are printed or embossed on the WSF and will form a part of WSF.

In one of the embodiments of this invention the security elements to be embedded in the WSF are added to the batch solution and mixed thoroughly before feeding it to the casting head for further processing. The materials that can be taken into the batch mixing are selected from those that are water-soluble, sheer insensitive, temperature resistant, like certain UV security dyes, or machine readable pigments.

In another embodiment of this invention the security elements to be embedded in the WSF may optionally be introduced at the primary, secondary, tertiary and subsequent sprayers and or at the second or subsequent casting heads fed from second and/or subsequent batch mixers.

In another embodiment of the present invention the security elements to be embedded is dispensed in between incoming cured or uncured WSFs.

In yet another embodiment of the present invention the security elements of overt nature such as holograms, barcodes are printed or embossed on the WSF.

Casting on the liner for manufacturing WSF embedded with security features by Batch Mix Method shown in FIG. 1 comprising of the following steps:

-   -   i. unwinding of the liner (1) at the unwinder (2) for the         formation of WSF. The liner can be optionally treated or         untreated and coated or uncoated. The liners can be of paper,         film, foil or fabric, preferably of film, more preferably of         polyester film. The film can be in the range of 2 microns to 500         microns, preferably in the range of 10 microns-300 microns, more         preferably in the range of 12 microns-250 microns. The film         liner may be plain, embossed, gloss, matt, extrusion coated         laminated or release coated depending on the desired         characteristics of the end product. The paper liner that accept         temperatures needed for production of WSF, may be in the range         of around 7 gms to around 500 gms, preferably a range of around         20 gm to around 300 gms, more preferably in the range of around         60 gm to around 180 gms. The paper liner may be plain, embossed,         gloss, matt, extrusion coated laminated or release coated         depending on the desired characteristics of the end product. The         fabric liner is made of cotton or synthetic yarns and solution         coated, plain, embossed, gloss, matte, extrusion coated or         laminated based on the desired end product properties.     -   ii. Optional coating of the liner with a primer via a primer         coating station (3).     -   iii. Casting of WSF on the liner at primary casting head (5)         with embedded security elements in the batch mix (4). The         temperature of the batch solution ranging from 10° C. to 95° C.,         preferably from 13° C. to 90° C., more preferably from 15° C. to         85° C.     -   iv. Metering of the cast film at the primary casting head (5).     -   v. Smoothening of the film by passing it through smoothening         rolls (7) with the embedded security elements at primary         station.     -   vi. Drying of the WSF from step 3 in the primary dryer section         (8). The temperature in the dryer section ranging from 50° C. to         250° C., preferably from 60° C. to 200° C., more preferably         75° C. to 170° C.     -   vii. Casting of another layer of WSF with or without the         security elements to be embedded at secondary casting head (12).     -   viii. Drying of the WSF from step 7 in the secondary dryer         section (13). The temperature in the secondary dryer section         ranging from 50° C. to 200° C., preferably 60° C. to 160° C.,         more preferably 75° C. to 170° C.     -   ix. The multi-layered WSF of step 8 is guided through         hot/chilled cylinder (20) for rewinding or splitting at rewinder         (21).

Optionally the above steps may also be carried out on a rolling conveyor instead of a liner.

Casting on the Liner for manufacturing WSF Embedded with security features by Application of Spraying Method shown in FIG. 1 comprising of the following steps:

-   -   i. Unwinding of the liner (1) at unwinder (2) for the formation         of WSF. Optionally a conveyor can be used instead of a liner.     -   ii. Optional coating of a primer on the liner via a primer         coating station (3).     -   iii. Casting of WSF with/without security elements to be         embedded at primary casting head (5).     -   iv. Metering of the cast film at primary casting head (5).     -   v. Spraying of pre-measured quantity of security elements to be         embedded by primary sprayer (6).     -   vi. Smoothening of the film with the embedded security elements         at primary station by passing it through smoothening rolls (7).     -   vii. Drying of the WSF of the above step 5 at the primary dryer         section (8). The temperature in the dryer section ranging from         50° C. to 250° C., preferably from 60° C. to 200° C., more         preferably from 75° C. to 170° C.     -   viii. Casting of WSF with or without security elements to be         embedded at secondary casting head (12).     -   ix. Drying of the WSF from step 8 in the secondary dryer section         (13). The temperature in the secondary dryer section ranging         from 50° C. to 200° C., preferably from 60° C. to 160° C., more         preferably from 75° C. to 170° C.     -   x. The multi-layered WSF of step 8 is guided through hot/chilled         cylinder (20) for rewinding or splitting at the rewinder.

Similarly, one or more security elements can be embedded into the WSF by the secondary, tertiary sprayers to form a multi-layered WSF embedded with security elements.

Casting on the Liner for manufacturing WSF embedded with security features by Online Entrapment Method as shown in FIG. 1 comprising of the following steps:

-   -   i. Unwinding of the liner (1) at the unwinder (2) for the         formation of WSF, optionally a conveyor can be used.     -   ii. Optional coating of primer on the liner via a primer coating         station (3).     -   iii. Casting of WSF with/without security elements to be         embedded at primary casting head (5).     -   iv. Metering of the cast film at casting head (5).     -   v. Smoothening of the film with/without the embedded security         elements at primary station by passing it through smoothening         rolls (7).     -   vi. Drying of the WSF from step 5 in the primary dryer section         (8). The temperature in the dryers ranging from 50° C. to 250°         C., preferably from 60° C. to 200° C., more preferably from         75° C. to 170° C.     -   vii. Casting of WSF with or without the security elements to be         embedded at secondary casting head (12).     -   viii. Drying of the WSF from step 7 in the secondary dryer         section (13). The temperature in the dryers ranging from 50° C.         to 200° C., preferably from 60° C. to 160° C., more preferably         from 75° C. to 140° C.     -   ix. Unwinding of a pre-formed WSF with or without liner from an         unwinder (18) and guiding it through the guide rolls (17) to         meet the WSF from step 8 for entrapping of security elements to         be embedded. Both the liners along with WSF film, which may be         semi-cured WSF and the entrapments, may remain in the roll form         or sheet form in its original construction, stripping from         casting liner can be done immediately or after an self-curing         ageing period ranging from around 1 hrs. to around 720 hrs.,         prior to splitting the liners so as to deliver the final WSF         product with entrapped materials. The preformed WSF used here         can be a WSF formed by the extrusion process.         -   The preformed WSF used here can be a WSF made by a cast             process or by extrusion process.     -   x. The multi-layered WSF of step 9 may be guided through         hot/chill cylinder (20) for rewinding or splitting at the         rewinder (21). Optionally offline or online splitting between         the WSF film and the liner can be done.

Offline Vertical Entrapment Method for manufacturing WSF embedded with security features as shown in FIG. 2 comprising of the following steps:

-   -   i. Unwinding of the preformed two water soluble films with or         without liner at the unwinders (22 and 28). The preformed WSF         used here can be a WSF formed by the extrusion process.     -   The preformed WSF used here can be a WSF made by a cast process         or by extrusion process.     -   ii. Dispensing of the security elements (25) vertically in         between two WSFs at guide rollers (24 and 26).     -   iii. Affixing of the two WSFs from step 2 at the affixing         rollers (23 and 27).     -   iv. Rewinding the multilayered WSF with security elements of         step (iii) in roll form or sheet form or fan-fold form. The         casting liners can be stripped immediately or after aging period         of around 1 to around 720 hrs. or can be supplied all together         and the end user may be informed to strip the casting liner         before use.

Offline Horizontal Entrapment Method for manufacturing WSF embedded with security features as shown in FIG. 3 comprising of the following steps:

-   -   i. Unwinding of the two WSF films with or without liner at the         unwinders (30 and 36). The preformed WSF used here can be a WSF         formed by the extrusion process.     -   ii. Dispensing of the security elements (33) horizontally in         between two WSFs at guide rollers (32 and 34).     -   iii. Affixing of the two WSFs from step 2 at the affixing         rollers (31 and 35).     -   iv. Rewinding the WSF with security elements, of step (iii) in         roll form or sheet form or fan-fold form. The casting liners can         be stripped immediately or after aging period of around 1 hour         to around 720 hours or can be supplied all together and the end         user may be informed to strip the casting liner before use.

The WSF embedded with security elements can be slit in ribbons, tapes, perforated sheets, perforated tapes, perforated ribbons or cut sheets of any size.

The WSF embedded with security elements slit into ribbons, tapes, etc. can be inserted into a package during the process of making pouch. The ribbons, tapes, etc. will destroy itself irreversibly during the final usage when the entire pouch along with its contents will dissolve itself in water.

Such methods offers various product options such as:

-   -   1. Entrapped security elements in WSF With or without         liner/carrier.     -   2. Entrapped security elements in WSF in Roll form or pouch         form.     -   3. Entrapped security elements in WSF in Roll form with         perforations.     -   4. Entrapped security elements in WSF in Sheet form with         multiple pouches.     -   5. All above Entrapped security elements in WSF with casting         liner for the consumer to remove after aging period of around 1         hr to around 720 hrs.

WSF film in the entrapment may be pre-embedded by means of batch mix or sprayer method or any other method explained above.

The above sequence may be repeated in multiple layers as per the requirements of the end use of the multiple WSFs embedded with security elements. Further this method also allows the manufacture of multilayered WSF embedded with security elements using combinations of Cold WSFs and Hot WSFs in various sequences. It also provides the options of using cured/uncured films of CWSFs and HWSFs in any desired sequences.

As per one of the embodiment, the overt security elements like holograms can be embedded into the WSF by directly embossing from a holographic plate/cylinder/shim on WSF. The WSF used for this purpose is preferably with a liner.

Holograms can also be embedded in the WSF with the hot stamping foil method or by transfer method, wherein the holographic film is coated with an adhesive and the adhesive side of the holographic film is laminated to the WSF.

Other overt security elements such as microtexts, barcodes can be embedded in the WSF by printing on the WSF itself. The printing of microtexts, barcodes can be done by known printing methods such as inkjet, gravure, flexo, web off-print and the like.

All security elements and WSF shall irreversibly destroy itself upon dissolution of package in water during final usage of the packed product.

As per the methods mentioned above one or more security elements having similar and/or dissimilar properties can be embedded into one or more layers of WSF to form a multi-layered WSF. Also, one or more security elements can be synthesized and can be added in the same layer of WSF. E.g. DNA taggants can be synthesized with florescent pigments for on-shelf checking of presence of fluorescent pigment DNA. Actual DNA presence has to be done off the shelf by a method of PCR readers.

Also, one or more security elements can be positioned at a prerequisite place so as to come up in the same place in the final package. This can be done by inserting a strip of HWSF/non soluble hydrophilic film embedded with security elements into the web of WSF during the process of casting the WSF. The other way of doing this is zone coating of a WSF batch mix embedded with security features onto a preformed WSF.

All security elements and WSF shall irreversibly destroy itself upon dissolution of package in water during final usage of the packed product. Covert security features like DNA, can be traced even after usage, for proof of usage of materials, by checking its presence at the place where the security film was destroyer such as soil or laundered clothes.

Security elements can also be mixed with printing inks and then particular designs or letters can be printed on the WSF. Here, the security elements will be present in the printed designs only and can be identified on the shelf or off the shelf depending upon the security elements embedded in the printing ink.

Example 1

10 ml of Tracetag DNA T7 TAG 1e*16 was added to 100 ml of florescent UV ink and mixed thoroughly. This synthesized mixture of security elements was then added to a 40 ltr batch-mix of WSF made out of the raw-materials mentioned herein before and mixed thoroughly. The batch mix consisting DNA and fluorescent UV ink was then cast on a liner as per the method described herein before to form a self-destructive irreversible security packaging WSF having thickness 45 microns. This security film can be used for various packaging purposes.

The presence of the fluorescent UV ink can be identified on the shelf under a UV reading lamp but for identifying the DNA, the package has to be carried to the laboratory and a separate process of covert forensic PCR checking is needed. The remnants of DNA taggants can also be checked after usage like in soil in case of agrochemicals and on washed clothes in case of a detergent package.

Example 2

100 ml of fluorescent UV ink was added to a 40 ltr batch-mix of WSF made out of the raw-materials mentioned herein before and mixed thoroughly. The batch mix consisting of fluorescent UV ink was then cast on a liner as per the above process to form a self-destructive irreversible security packaging WSF having a thickness of 35 microns. The same WSF with fluorescent UV ink was embossed with holograms at prerequisite places. The holograms are visible instantaneously while the presence of the fluorescent UV ink can be identified under a UV reading lamp. Hence, here both the security features can be identified on the shelf. During the process of final usage of the package, the same shall dissolve, disintegrate and shall irreversibly destroy itself.

Example 3

RFID tags were printed at prerequisite places on a hot water soluble film. This HWSF printed with RFID tags was then accurately cut into thin strips of 20 mm width. A strip of HWSF printed with RFID was then positioned and inserted into a web of CWSF during the process of casting the CWSF. This security element can be read by RFID machine reader which has been specifically designed to read the outcome. During the process of final usage of the package, the same shall dissolve, disintegrate and shall irreversibly destroy itself.

It is now clear that the self-destructive security packaging film can be produced by methods mentioned herein before and that the same can be used to secure various types of packages to ensure that the rightful owner gets their earnings and the fraudsters are dealt with properly by the legal/Judiciary systems prevailing in respective countries.

Such security elements embedded WSFs are used for diverse applications, such as, but not limited to, embedding such WSF into a bed of pulp to make security paper, or to make a pouch or a web or a slit tape or any article from such a security film to deliver pesticides, seeds, drugs, veterinary products, agrochemicals, perfumes, softeners, flavors, detergents, etc, so as to identify the products while on the shelf as well as after consumption by reading the reactions of the security elements while the package is intact or reading the reactions of the security elements after the package has been dissolved and traces of such security elements can be observed on the used areas of the product which can be for example soil in case of agrochemicals/seeds or garments in case of detergents, softeners etc.

A security element embedded WSF can also be converted into self-adhesive web and subsequentially converted into a printed seal with a barcode, including a 2D or 3D barcode. This self-adhesive label/seal can be applied for example to secure the opening of a package or a bottle with instructions to dissolve seal in water to open the package. 

The invention claimed is:
 1. A method for manufacturing a water soluble film (WSF) carrying at least one security element incorporated in at least one layer of said WSF, said method comprising the steps of: forming a mixture by adding one or more security elements into at least one batch mixer containing a batch solution of the WSF, the batch solution having a temperature ranging from 10° C. to 95° C.; mixing the mixture thoroughly; feeding the mixture to primary or subsequent casting heads for further processing for forming a WSF having said one or more security element embedded in at least one layer of said WSF; unwinding a liner from an unwinder and casting said mixture on said liner to form a first WSF layer on the liner; drying the first film layer in a primary dryer section, wherein the temperature in the primary dryer section ranges from 50° C. to 250° C.; casting a second layer of said mixture on top of said first WSF layer to form a second WSF layer; drying the second WSF layer in a secondary dryer section wherein the temperature in the secondary dryer section ranges from 50° C. to 250° C.; and stripping said liner immediately or after a self-curing, ageing period ranging from 1 to 720 hours; wherein the method further includes adding an overt security element to the film by one of the following steps: mixing at least one security element in printing ink and printing letters or graphics on said WSF, wherein said printing ink comprises said at least one security element of said WSF; imprinting or imparting at least one security element on the WSF, said imprinting or imparting step being selected from the group consisting of a hot stamping foil method and an adhesive transfer method; or incorporating at least one security element in the WSF by printing said at least one security element on said WSF by a method selected from the group consisting of ink jet, flexo, gravure, and web offset.
 2. The method according to claim 1, further comprising the step of slitting said WSF in a form selected from the group consisting of ribbons, tapes, perforated sheets, perforated tapes, perforated ribbons and cut sheets of any size.
 3. The method according to claim 1, wherein said WSF incorporated with said at least one security element is in a form selected from the group consisting of sheet form, roll form and pouch form.
 4. The method according to claim 1 wherein the temperature in the primary and secondary dryer sections ranges from 60° C. to 200° C., wherein the temperature of the batch solution ranges from 13° C. to 90° C., and wherein an overt security element that is imprinted or imparted is a hologram.
 5. The method according to claim 4, wherein the temperature in the primary and secondary dryer sections ranges from 75° C. to 170° C. and wherein the temperature of the batch solution ranges from 15° C. to 85° C. 